Vacuum cleaners of the canister type are disclosed in a number of U.S. patents. Those of which I am aware include may earlier issued patents identified above and U.S. patents Nos. 1,573,771 to McClatchie; 2,433,356 to French; 2,438,133 to Sparklin; 2,591,305 to Segesman; 2,634,451 to Dow; 3,002,215 to MacFarland; 3,023,838 to Gaudry; 3,089,177 to Andersson-Sason; 3,142,857 to Fresard et. al.; 3,270,365 to Waters et al.; 3,328,826 to Amos; and 3,621,640 to Ohno et al.
Canister type vacuum cleaners generally consist of a motor and a vacuum pump, a compartment housing a dust filter, a suction hose, an assortment of cleaning tools, a power cord and switch, and a tanklike casing or canister. The motor and pump, dust filter, and power switch are usually located in the canister of the cleaner with the hose communicating through one end of the canister with the dust filter compartment and the power cord entering the canister at the opposite end.
The canisters of such vacuum cleaners are usually horizontally oriented cylinders or polygonal like boxes and spheres oriented in a variety of attitudes.
To facilitate movement over rugs, bare floors, thresholds, etc., canisters, wheels, runners, pneumatic flotation elements, glides, etc., are usually attached to the canisters. Also, elastomeric bumpers are usually provided to reduce contact with furniture and the like. Further, a handle is provided to facilitate carrying the canister from place to place.
Because they protrude from the canister, casters and the like, bumper strips, and handles become engaged with rug edges, thresholds, rocker runners, furniture legs and feet, etc. They also cause the canister to move in undesired directions, defeating their purpose.
Conventional canister type cleaners also have protruding knobs, hinges, latches, etc. and a protrusion at the hose junction, all of which are apt to catch on table and chair legs, sharp corners of furnishings, etc.
These inconvenient and vexatious situations are often compounded by the cleaner being upset when the user tries to dislodge the machine. Then, he must stop to right the machine or drag the cleaner in its upset attitude, which increases its tendency to hang up on obstacles and makes the power switch inaccessible or very inconvenient to reach.
In addition to the foregoing inadequacies, the usual canister type cleaner is low to the floor and provides a poor and inconvenient platform upon which to drape the hose and/or to support the conventional, relatively long, rigid wand. This results in a generally unkempt sprawl of vacuum cleaner and appendages on the floor of the storage area.
My prior patents Nos. 3,883,922 and 3,950,814 disclose certain novel, improved vacuum cleaners of the canister type which do not have the above-enumerated drawbacks. Briefly, those novel vacuum cleaners include an elongated body or casing contoured so that the cleaner will glide easily across the surface of the area being cleaned. Preferably, the contour will be selected so that the cleaner can glide easily on its top and sides as well as its bottom, thereby making it orientation insensitive.
A detachable, wheeled dolly can be coupled to the vacuum cleaner to increase its mobility. Unfortunately, this dolly limits the number of orientations which the vacuum cleaner can usefully assume when the dolly is coupled to the vacuum cleaner.This makes the vacuum cleaners disclosed in my issued patents significantly less versatile when the dolly is attached than they are when that component is absent.